Trust influences interactions among individuals and organizations but has been an elusive concept to define and measure. The Organizational Trust Inventory (OTI) measures three dimensions of organizational trust, as defined by Cummings and Bromiley (in: Kramer and Tyler (eds) Trust in Organizations, 1996), believing or feeling that others: keep commitments, negotiate honestly, and do not take excessive advantage. This research presents an original adaptation of the OTI for the Italian people. It can now be used to evaluate trust regarding colleagues, managers, suppliers, subordinates, clients, and organizations. Using a sample of 490 employees and structural equation modeling, we consider the validity of the questionnaire and the theoretical model articulation both across different counterpart and countries. Besides, we develop a new reduced-form of the questionnaire (OTI/R), which offers better psychometric properties than the long form.